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hypnosec writes "Researchers at University College of London have applied principles of radar used in defense and designed a detector using home based Wi-Fi routers to spy on people across walls. Using the principles behind the Doppler effect ... Karl Woodbridge and Kevin Chetty, at University College London, have built a prototype unit that uses Wi-Fi signals and recognizes frequency changes to detect moving objects. The size of the prototype unit is more or less the size of a suitcase. The unit contains a radio receiver comprising of two antennas and a signal-processing unit. The duo carried out test runs and ... they managed to determine a person's location, speed, and direction (even through a one foot thick brick wall). The device could be used to spot intruders, monitor children or the elderly, and could even be used in military applications."

I hope cloning food is one of those glitches that will end up as a feature someday, like rocket jumping. At any rate, since he shared the bread and fishes with all on the server, I wouldn't call it abusing the bug, especially since they were all just idling anyway, there wasn't a match in progress at that time.

At any rate, since he shared the bread and fishes with all on the server, I wouldn't call it abusing the bug, especially since they were all just idling anyway, there wasn't a match in progress at that time.

Some other cases of him exploting glitches also come to mind. But being a son of the server admin, I don't think there was any chance of him getting banned...

Well yeah, there's that ^^ But as I said, I don't think it counts as cheating, since he wasn't really fragging anyone... IIRC he mostly warned of the impending crash of the server they were on, while handing out the access details for the new one ("the admin's private server has many slots") to those who agreed to installing punkbuster and having their score reset. He exploited glitches to get the attention of players for that purpose, sure, but I'm not sure that sounds as cheating?

I dunno, in the end the Roman Empire guild crucified him after all.Besides its not entirely clear that he was the son of the server admin, there's been these confusing references to an account named Holy Ghost, as well as the Jesus account and the Admin account itself of course, suggesting that all three are "one, but separate" etc. Might be the same player administering the server and then playing on 2 other accounts as well.

Didn't Jesus let them kill him on purpose, so he could respawn 3 days later as a further demonstration of him being (endorsed by) the admin? But yeah, it's hard to make sense of it going just by a bunch of server logs which may have been tampered with.

As for the partial server logs, remember that whole confusing "I come not to bring peace, but to bring a sword" statement when all along he claimed to be uninterested in PvP entirely? Very confusing.His followers seemed to be heavily into PvP mind you...

Or he lectured the crowd for hours about not beeing greedy and sharing with others before announcing that they didn't have enough food to go around... and surprise! many of the people had brought their lunches and decided to share.

Nope, I've got to go with sound primarily, followed by movements faster than a typical zombie. This conclusion is the result of many hours of studying documentary footage of zombies hunting in their natural habitat.

You forgot ghosts! If it detects vaguely moving, inaccurately shaped blobs through a wall but isn't real clear if something is really there or not and it can't tell the difference between an owl, a coffee table, and a human, the Ghost Hunters will be all over it! This will spark a whole new series of their show! ERMEHGERD!!! BLOB! MUST B GHOSTZ!

In the 1930s, U.S. Navy researchers stumbled upon the concept of radar when...

Rubish. The US Navy did not invent radar as it implies. Nicola Tesla descibed the concept in 1917 and others were playing with similar ideas before then. Sorry. Im not going to bother reading the rest. Isnt there an actual paper on the subject we can read instead of this badly-informed junk?

Rubbish ^2 - The quote does not imply the navy invented radar. "Stumbled upon the concept" directly implies the concept already existed, ie: the Navy heard about it in the 1930's and put it to practical use. Even then, nobody was really interested until WW2.

So does that mean if I'm exploring out in the woods, and I stumble upon a cave entrance, that the cave didn't exist prior to my discovery?If I'm researching some technology and I stumble upon a related patent, that the patent didn't exist before I found it? Great, that means I just need to stumble across every patent in the USPTO, and I own every technology in existence!!

Screw the rest of the steps, just:

5. PROFIT!!!!1!

Your interpretation is completely at odds with decades of history of this phrase.

No it doesn't. Stumbled upon the concept implies the concept was NOT there before, and while researching a related matter, somone had the idea of radar, independantly. So, the quote does indeed suggest that the navy invented radar.

Incorrect. Stumbling upon something literally refers to the act of coming upon something; it does not imply existence of that something either way, not that that something existed before, nor that that something didn't exist before. You can stumble upon radar technology itself just as much as you can stumble upon the fact that someone else stumbled upon it.

Unlikely. The majority of people are platonists, and believe that all ideas "exist" already out there in some universe of the mind, and that people merely discover (or "stumble" upon, if the discovery is incidental) them.

Of course it is literally impossible to stumble upon radar technology, or upon the fact that someone else stumbled upon it, figuratively.

Maybe they did? I'm not making any specific claims. I'm just offering an alternative interpretation of the quote that upset the OP so much that he "stopped reading". Doing that based on the quote alone is a bit like not reading a newspaper because it includes a horoscope.

Umm... not only that, but I know of NO such described incident with regard to the US Navy.

I DO know of such an incident in the UK, which occurred while they were experimenting with attempts to interfere with aircraft engines using radio waves. It was this that started Thomas Watson-Watt and the other UK scientists off on their eventual invention of Radar.

The US had nothing like this, and did not do any research in the field. I think that this item is just transposing something that happened in the UK and claiming that it happened in the US - something the Americans frequently do....

Allow me to recommend "Man of High Fidelity: Edwin Howard Armstrong" by Lawrence Lessing, and specifically direct your attention to the part that covers Major Armstrong's service in the U.S. Army Signal Corps during World War I.

Hi there. NSA here.
We'd like to ask everyone to stop copying our ideas. Unfortunately we can't patent them for obvious reasons, but we can block you just as much under the 'National Security' stamp, so just forget about it. Also just letting you know we are pushing for legislation to ban auto-frequency shifting routers and any rapidly moving iron object in the premises that may scatter signals.
But for the record; this works just as well with your cordless phone, cellphone, radio controlled car and microwave, so switching of your router really doesn't help you. And since you propagate the radio signals voluntarily the fourth amendment also doesn't apply. (Please don't conclude we care about the constitution - We've had this argument already)
Oh yeah, before I forget; dwellings that emit NO radio signals are automatically marked for surveillance and occupants placed on the no-fly list.

Hi there. NSA here. We'd like to ask everyone to stop copying our ideas. Unfortunately we can't patent them for obvious reasons, but we can block you just as much under the 'National Security' stamp, so just forget about it.

http://en.wikipedia.org/wiki/Invention_Secrecy_Act [wikipedia.org] You can apply for a classified patent and the government can retroactively classify an already granted/applied for patent.Once your patent is classified, your only customer is the government or government contractors with clearance.

When I saw this article, I immediately thought of something I had seen done for years.

Basically, this device is a digital signal processor looking at two antennas and looking at the phase shifts induced by a moving reflective object.

The effect is quite pronounced, and only needs some source of RF to illuminate the area. An OTA TV transmitter transmitting its normal fare does very nicely. If you have ever used a TV with rabbit ears, I am sure you have seen the effect yourself. You move about the room

whoa, whoa cowboy, slow down there....that last "even" just made the entire rest of the article padded filler to justify what anyone would expect anyway, but seeing it couched in such pathetically blatant terms only makes it stand out all the more. We all saw Real Genius son, we all know how this works, you're not on our side.

Passive radar has been researched and used for a while now, which is cool. And the reported thing would be cool too, if it would be passive and if it would not require a custom-built active-signal based wifi device with the size of a suitcase which is anything but covert. Also, through-the-wall radars have been used for a time, which don't provide too much detail, but can tell at least the number of moving objects and locate them. Again, this would be quite nice if it wouldn't require the placement of a custom device, or if it does, then it should be quite much smaller and not different in size or looks from any other router you can buy, and then at least they could place them in banks or wherever.

Passive radar uses radio sources, like TV and FM stations, instead of having its own transmitter. The receiver detects the direct signal from the transmitter and the signal reflected from the target. The trick is to separate the two. Using the doppler effect does that nicely for moving targets.

The advantage of passive radar is that it can't be detected.

The radar in TFA doesn't need to be undetectable, the targets probably don't have detectors. It could have its own transmitter. That would simplify the receiver design a lot. The transmitter is quite simple and cheap, being a GUNN diode or something like that. It would also require a directional transmitting antenna. Developing such a device would be much cheaper and it would work much better.

Given that the researchers did the job the hard way, their accomplishment is quite impressive. On the other hand, we haven't seen a fully field tested version. There is a large gap between a lab demo under controlled circumstances and an actual useable device.

You are worried about TR-069?!? At least with TR-069 you know the equipment vendors and operators have a convention to allow only some remote provisioning... I mean, if they were devious, they could compile in back doors instead of TR-069. The farmacy has a pill that will make them stop chasing you.

So if it uses Wifi-range signals, we could prolly make a "spy device detector" or even "spy device blocker" in dd-wrt?With everyone using wifi, I don't understand how results could be so accurate. Please enlighten me:)

While it is super neat to see this being done with routers by mere humans, it hardly compares to what our overlords have been doing for a long time. An old friend who was a low-level translator for the NSA (spying on Russians), had once described a patented device which was used for remote eavesdropping. For example, it would use the radiation from something like a television, or a monitor, etc., and through extremely sensitive observation, determine words by the electro-magnetic interference caused by the

... initiate a call to the perps, precisely triangulate the location of the phone source through common RF firection finding, use passive detection using your own cell and responding perps cell signals (add in others for more precision). Would have been complicated to do once upon a time but tech is there to do it now. Reply to this post if you want to take this idea to market:-)